In　order　to　improve　the　architecture　luminous　environment　and　indoor　air　quality,　solar　light-vent　pipe　systems　are　researched　and　developed.　Two　different　self-made　solar　light-vent　pipe　systems,　＇Direct＇　and　＇T＇　type,　are　tested　with　the　tracer　gas　concentration　decay　method.　The　ventilation　performance　of　the　two　devices　is　compared　with　different　inlet　opening　under　the　same　temperature　differential　conditions.　Experimental　results　show　that　the　type　of　solar　light-vent　pipe　systems　and　the　opening　of　air　inlet　have　significant　impact　on　the　ventilation　effect.　The　decay　time　of　＇T＇　type　is　longer　than　the　＇Direct＇　type.　The　opening　of　the　inlet　is　bigger,　the　speed　of　decay　time　of　the　tracer　gas　is　faster.　The　illuminance　is　more　than　100lux　under　20　cm　of　the　diffuser　of　solar　light　pipes,　which　can　meet　the　need　of　daylighting.　The　tracer　gas　concentration　decay　method　is　one　of　the　effective　means　to　study　solar　light-vent　pipe　systems　and　the　＇T＇　type　solar　light-vent　pipe　has　better　natural　ventilation　effect.